“The ‘Do not show the Start Menu when the user logs in’ policy allows you to boot the OS into the more familiar desktop and not the Metro start menu. Interesting to note that booting into the desktop is also the default behaviour for Windows Server 8 so you can also use this setting on your server if you want to start them into Metro (but you prob don’t want to).”

Update: This might not be as promising as Burchill originally thought. He has amended his post to note that this setting may be a server-only thing.
While many love the tiled Metro start screen and are looking forward to using it on touch tablets and PCs, many others aren’t keen on it — especially business users who are convinced that Metro will be nothing but a nuisance, especially on non-touch-enabled hardware, and that they’ll do most of their work in the Desktop app on Windows 8.